There have been quite a few reports in recent times pointing to the lack of viewability of online display advertising, and I’ve blogged about this topic before.

And now, we have the $55-billion “advertising vacuum-cleaner company” Google itself admitting as much.

It comes in a study that Google has just released. The report presents findings from its analysis of display ad programs using its “active view” technology (like DoubleClick) to determine which factors are affecting the viewability of ads.

The results aren’t pretty; more on that below.

But first … why is Google doing this?

I suspect it’s because more advertisers are now insisting on paying only for their ads that have been actually viewed, as compared to those simply served.

Now, to what Google is reporting. It turns out that fewer than half of all ad impressions served on Google’s display platforms are ever seen, because they’re served outside of the viewer’s browser window.

That is correct: A huge chunk of Google’s billions in ad revenues that it collects come from ads that no one ever saw.

What digital advertising platforms love to remind us is that their programs are superior to “bad old television and radio advertising” because of their sophisticated targeting capabilities and their superior measurement metrics.

That may be. But how is it all that different for TV viewers to miss an ad because they took a kitchen or bathroom break, compared to people who never even had the opportunity to see an ad that was “served” in a dead zone?

The next question is, “What can advertisers do to help minimize the incidence of phantom online advertising?”

Helpfully, Google provides some clues in its report. For instance, the highest viewability for ads is immediately above the “fold” – in other words, at the point where the viewer must begin to scroll down to see the rest of the page.

Surprisingly, viewability right above the fold is slightly higher than at the very top of the page. But it’s massively less so just below that magic spot. Google pressented five charts in its report to illustrate this drop-off phenomenon; the one reproduced below shows viewability of vertical position ads sized 728 x 90 pixels:

Less surprising, perhaps, is the fact that vertical ads have higher viewability than horizontal or block ads, for the simple reason that they stay on the page longer:

By publishing this data, Google purports to want to help their advertisers understand high- and low-value inventory better so they can target their campaigns more appropriately and effectively.

Google is also encouraging publishers to strive for delivering viewability rates in excess of 50% by offering ad inventory that will perform more effectively in its respective positions.

My only question is … why has it taken Google so long to set these standards and to publicize them in the first instance?

Sure, Google’s only the middleman between publishers and their viewers. But it’s a pivotally important one.